Isotopic cross sections in fragmentation reactions of C12,14, N14

Systematic measurements of 51 isotopic cross sections from fragmentation reactions of 240 MeV/nucleon $^{12,14}\mathrm{C}$, $^{14,16}\mathrm{N}$, and $^{16}\mathrm{O}$ projectiles on a carbon target were performed at the RIBLL2 separator and the external target facility (ETF) of the Heavy-Ion Research Facility in Lanzhou (HIRFL). Our experimental cross sections produced by fragmentation of three stable projectiles, i.e., $^{12}\mathrm{C}$, $^{14}\mathrm{N}$, and $^{16}\mathrm{O}$, were compared with some previous experimental data measured at different energies. The comparison indicates that our experimental data are in generally good agreement with previous experimental data. Tens of new isotopic cross sections produced by fragmentation of two unstable projectiles $^{14}\mathrm{C}$ and $^{16}\mathrm{N}$ were also measured in this work. All cross sections measured in this work were used for benchmarking three fragmentation models, i.e., ABRABLA, NUCFRG, and FRACS. Most experimental data can be well reproduced by these fragmentation models, but there are severe discrepancies for some isotopic cross sections from fragmentation of unstable projectiles.